I wanna weld the 3 pieces of my narrowed '56 wagon bumper into one. I already shaved the bolts in the center section. The problem is that none of the pieces are even a close match, typical factory variations in the none too accurate '50s. I want to run my exhaust through the ends too, it will give me a few inches of ground clearance. I don't want to end up with tell tale lines and stuff. FBS plating down here aren't too keen about plating other folks work, it's understandable, but they do good work. The bumper ends were from Bumper Boyz and the plating started peeling from the day I put them on. I guess I just have to build up the dips and valleys with weld, huh? Do you reckon it would be best to do the work with the bumper firmly bolted to the car? The bumper also has a '49 Chevy license surround that would look great molded, but I'm worried about how good the plating will be in the nooks and crannies. Also how much slack in workmanship can copper compensate for? Thanks.
Bolt it to the car to get your basic tack welds in place for fitment(TM). Pull it off and bolt to a couple of saw horses for all of the final weld and grinding. I've seen br*** used for the final fill and valleys. Hope it helps.
Hey Mike that's what I did the first time around, futt bugly, but that's all I could afford. I think the time to do this is now, even if I can't get the thing rechromed right away I'll put some chrome paint on the joints to get by.
Made up a few bumpers before. First thing is to have the chrome stripped off. Most chrome shops can do this for you fairly cheaply. Next I would cut the bumper sections where they join together. The mounting flange will keep you from forming the bumper when you weld the pieces. Keep everything square and pay attention to any ridges or profile lines in the center of the bumpers. Edges are easy to fudge with a big angle grinder or portable belt sander after you weld it. Bumper material will work fairly easy with a big hammer. When I built the front bumper for my truck I used two completely different ones, the outer ends are 70's Ford Van and the center was a right half of a 63 Ford truck. They were similar in profile (cross section) but not perfect. I just used some body working skills and a BFH to get them to match up. I tig welded most of it with regular steel wire. I did make a mistake using silicon/bronze wire to fill small voids instead of more steel and when it was chromed the areas where the bronze is stood out as a seam. MIG welding would be just fine for most of what you are doing, just be very carefull when you grind and sand everything to get the best contour. I would use a flap disc to remove most of the metal in your case. Check your work with a large file, any high or low spots will show up pretty fast. And of course the smoother the finish the better the chrome will look and the less work your plater will have to do.
ElP, thanks for the tips man. I was thinking I oughta cut the flanges off, if I do I'm sure I can get the pieces to line up good. Also the whole shebang really needs to be widened just a smidge, because I cut it too short the first time. Will it help to put some strap behind the welds for reinforcement? Can you also tell me what I did wrong with my bumper bolt shaving? There are telltale marks of where they used to be, it's beyond the actual bolt, it's like the whole area surrounding the weld sort of caved in. It doesn't look good, and I'm gonna be honest I ran the whole bumper off just those two bolts for a few weeks until I fabbed the end irons, that's probably what caused it. I only use flap wheels now, they work a kabillion times better than grinding wheels. Would it be OK just to grind the chrome off the areas I'm welding or should the whole thing be dechromed chemically?
You don't need to put the strap behind the weld, just weld both sides of the joint. I ***ume when you mean you can see depressions where the bolts are, that there were no depressions there before but appeared over time. Best solution it to slip a large washer over the bolt and then weld it to the bolt and the perimiter of the washer. This will spread the load out over a larger area. And you should have more than two bolts holding it on. I usually do two bolts per side and place them on a diagonal. It also helps to have supports from the frame to the bumper tips to keep the bumper from vibrating. Less vibration means a quieter car and the weld joints won't stress as much making the bumper last longer. I am sure our resident metalurgist could give better insight to the chrome removeal and contamination question but honestly I havent' ever had a problem welding through chrome. I have cut many of my Craftsman wrenches in half and then welded them together with stainless steel filler rod (TIG) and then buffed the affected area. To this day I have never had one come apart. But related to the bumper thing, I like to remove as much chrome as possible just in case there is a problem. Not to mention it makes it a hell of a lot easier to finish the surface when there is no chrome to deal with. One last tip,, I have the bumper sand blasted inside and out before I take them to the plater. This makes sure there is no rust or slag on the surface and results in a better chrome finish AND the back side of the bumper looks much better. Not like that matters much but I have seen way to many high end cars that the front side of the bumper was perfect and the backside was flaky and scaley with old chrome, looks bad.
FWIW, After the horror story I had with the plater that did my bumpers, he told me I should have left the welds a little low, then filled them with br***. For the low spots at the shaved bolts, most people don't realize that you shouldn't torque bumper bolts nearly as much as you think. I have heard it sugggested to put a piece of heater hose or similar over the bumper bolt after the bolt is fed thru the bumber arm/bracket. Then stack a flat washer, a lock washer, then the nut. This gives you a little cushion to prevent over-tightening. You could use a nylok nut in place of the lock washer/std. nut if you prefer. And everything that ElP said, too.
Thanks for all your help, I love the HAMB. I do have supports running across the bars. The extensions on the bumper bars were made with regular steel not spring steel like the originals. I didn't know the original bars were spring steel until I tried to cut them with my Sazall, Holy Cow that didn't work at all. I'll put the progress of this job on the HAMB for tech week, see I'm not just a resident blowhard.
From what I read it is ok to fill in little imperfections with br***, but not with bronze. How about lead or pure tin? Would be easy to bring to a nice surface. Any thoughts?
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